1-Hydroxybenzotriazole → HCID 15385777, compound

Participants

Reaction Steps

To a stirring suspension of EtSO2-D-Phe-OH (25.7 g, 100 mmol), Pro-OBn.HCl (26.6 g, 110 mmol), HOBT (13.5 g, 100 mmol) and N,N-diisopropylethylamine (43.5 mL, 250 mL) in THF (1 L) at 0° C. was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (23 g, 120 mL). After stirring for 20 h, the solvent was removed in vacuo and the residue was partitioned between ethyl acetate and 1 N citric acid. The organic phase was washed twice with 1 N KHCO3, twice with brine, dried with MgSO4, filtered and concentrated in vacuo. The residue was chromatographed over silica gel, eluting with a step gradient of hexanes through 50% ethyl acetate/hexanes. The product containing fractions were combined and concentrated in vacuo to give 29 g (65%) of a clear, thick oil.

Provenance & Evidence